This invention relates generally to high power semiconductor laser arrays and more particularly to high power semiconductors laser arrays mounted and collimated in such a way that a single spot of high intensity light is produced.
In numerous applications such as laser tracking, laser guidance and laser imaging, it is desirable to produce a high power coherent laser output. In the past, single semiconductor lasers were utilized to provide a coherent source of laser output. Such single semiconductor lasers were limited in the amount of power which they could provide due to their structural limitations and limited efficiency. Arrays of semiconductor lasers have also been utilized where adjacent emitters of the array of semiconductor lasers spaced upon the same substrate would be coupled together such that a known angular displacement would exist between the output of the adjacent emitters. In this fashion, a coherent laser output beam of a slightly higher power could be provided.
Typically, such arrays of semiconductor lasers suffered from several deficiencies. One such deficiency was the necessity for a bulky power supply or a specially designed power supply from which to power the array of semiconductor lasers. This bulkier, specially designed power supply decreases the mobility of the semiconductor laser array as well as increasing the expense of fabrication. An additional deficiency was the inability to precisely collimate and focus the output of the laser array such that the adjacent beams could be overlapped to create a very high light intensity.
Additionally, many other semiconductor laser arrays utilize multimode laser devices which were unable to form a tight single spot of laser light but instead produced a larger, less intense laser output. Another deficiency with typical semiconductor laser arrays is the inconsistent thickness of the bond formed between the laser array and the mounting structure or heat sink. This inconsistency, typically caused by irregularities in the bonding material utilized, cause the output of the laser array to be misaligned and not form a single spot of high intensity laser output.
It would be desirable for a semiconductor laser array to produce a single spot of high intensity laser output from a small power supply that is not bulky or does not require a special design. Furthermore, it would be desirable for a semiconductor laser array to be mounted evenly and collimated such that the laser output's fill the aperture available to provide a substantially constant intensity across the single spot of laser output produced.